full-scale resistance option of the popular DS1859 SFP controller/monitor.
Similar to the current DS1859-050 (50k full-scale resistance option), the DS1859-020 controls laser-driver bias and modulation currents, while also managing system monitoring functions required for SFF-8472-compliant optical transceivers. The new 20k resistance option provides higher adjustment resolution, which is optimal for calibrating some laser drivers.
The DS1859's high level of integration reduces component count and layout area, and speeds up the design of optical transceivers. Control functionality is comprised of two 256-position, nonvolatile (NV) variable resistors with customer-programmed, temperature-indexed EEPROM lookup tables.
An integrated 12-bit analog-to-digital converter (ADC), temperature sensor, and MSA-compliant register and memory architecture provide SFF-8472 diagnostics monitoring functionality. The device monitors three external analog signals, as well as VCC and temperature. Programmable alarm and warning trip points for all monitored signals alert the system to out-of-tolerance conditions. Additional device features are internal calibration and ADC ranging to increase the dynamic range for received optical power measurement. Communication with the devices is achieved over a 2-wire serial interface.
The DS1859 is available in a space-saving 4x4 BGA package (0.8mm pitch) or 16-pin TSSOP. It operates from a 2.7V to 5.5V power supply over a -40°C to +95°C temperature range. An evaluation kit is available.
Additional Information:
QuickView Data Sheet
Full Data Sheet (PDF)
